The attached patch improves pg_ctl's win32 service code to eliminate
some possible causes of the stale postmaster.pid problem that some users
have reported.
- The service did not properly report that it accepts
SERVICE_CONTROL_SHUTDOWN events, thus it's possible the SCM simply
killed the postmaster on shutdown.
- 'WaitHints' are now given to the SCM to prevent it timing out if
pg_ctl doesn't respond to a control event quickly enough.
- During shutdown, the service checkpoint counter is incremented every
five seconds for up to a minute to prevent the SCM timing out and
assuming the service is not responding.